Reference Tables

Stable engineering reference data: the AWG wire chart, NEC 310.16 ampacity, EMT conduit fill, voltage drop per gauge, copper/aluminum resistivity, NREL peak sun hours and typical appliance wattage.

AWG Wire Size Chart: Circular Mils, Resistance & Ampacity

American Wire Gauge geometry and resistance — circular mils, ohms per 1,000 ft for copper and aluminum, and the NEC 310.16 ampacity at 75°C.

NEC 310.16 Ampacity Chart (60 / 75 / 90°C, Cu & Al)

Allowable ampacity of insulated conductors per NEC Table 310.16 — copper at 60/75/90°C and aluminum at 75°C. Confirm the NEC edition adopted by your AHJ and apply all derating.

EMT Conduit Fill Chart: Areas & 40% Fill

EMT conduit cross-section, the 40% fill area (more than two conductors) per NEC Chapter 9, and the maximum number of #12 and #10 THHN conductors.

Voltage Drop Chart per AWG (20 A, 100 ft, 120 V)

Voltage drop by conductor size at 20 amps over a 100-foot one-way run on a 120 V single-phase copper circuit — a quick reference for the 3% guideline.

Wire Resistivity: Copper & Aluminum K Factor

The resistivity constant K (circular-mil-ohms per foot) for copper and aluminum used in the voltage-drop and wire-resistance formulas.

Peak Sun Hours by US State (NREL Average)

Average peak sun hours per day by US state (NREL geographic average) — the divisor for solar array sizing. Design for the worst month for year-round off-grid.

Appliance Wattage Chart: Running vs Starting Watts

Typical running and starting (surge) watts for common household and RV appliances — for generator, inverter and battery sizing. Estimates; read the nameplate.